You can now use aws-serverless-express, an open source Node.js library, to simplify the migration of your Express web applications and REST APIs to a serverless architecture. The library is built using features from Amazon API Gateway that allow you to preserve your API routes in your existing web application frameworks without having to redefine API methods or their integration behavior on API Gateway.

This package contains a working example that you can use as a starting point for your own application. Read more on our blog.